if you do the cheep fix you will get the cheep result

 

it's just a patch, and i did try alumaseal after all this hullabaloo on a personal car that lost a coolant seal after this thread. but again, was on a later model 13B iron based coolant seal engine. in fact it got to the point i couldn't even get the engine to start anymore.

didn't work, didn't even attempt to work. i couldn't find any alumaseal designed for combustion either, they are just radiator stop leak products. i have had better personal results with copper head gasket sealant(think Bar's leak) on post '86 engines that i personally owned and gimped along for a while. leave it in the radiator with zero coolant and all water, drive it around for a bit with it in the cooling system shutting it down after it is warmed up, cool it off, rinse and repeat.

 

I tore it out yesterday and stripped the motor down. I am ready to split it open. I couldn't believe how easy it was to get out and tear down to this point. I do have use of a full shop with a lift though....that definitely helps But I am a bit nervous of pulling the cases apart...I'm guessing it is a bit harder.

I wish I had a detailed instruction manual handywith clearances and such. I do have a Haynes manual, but was shooting for something better. If you guys know of a link please feel free to shoot it over to me. I plan on going to the shop today and tearing it apart. I want to figure out what I need to replace, and just replace those issues. If something else fails I can replace it at a later date, after hitting the lottery. But right now I have too many projects and want to get those done and sold....then look for somewhere I can race this thing I think.

 

A couple of weeks ago, Hecubus84 (I think I've got that right) came over to my side of the state for an autocross. He's got an fb with a 2nd gen 13b transplant, and was complaining of starting issues due to coolant seeping into the housings.

I gave him 1/2 a bottle of alumaseal, and the effect was damn near instantaneous. We left my place, drove to Denny's for a pre-race breakfast, and upon leaving the car started instantly and without issue. So, add another success to the list of 13b attempts.

Once again, I'll say that it all depends on how the seal failed, and the direction of flow.

Also, again, I'm up to 40,000 miles on my own repair on my 12a. Still my daily driver, still tearing up the competition at the races. Temporary repair? Well, I'll be sure to let you all know when the motor finally gives up the ghost, but in the meantime I'm 3 years and 40,000 miles down the road on my "bad" engine.

 

Kentetsu, I just de smogged rebuilt carb, and headered a just acquired 85 12a that previously idled but ran poorly, albeit with no smoke. Upon firing up I seem to have the coolant seal issue, abundant white smoke. With a wife and 4 kids, alumaseal sounds great! Thanks for your research and posts regarding it.

 

The clearances in the Haynes are just a copy and paste from those in the FSM. If you prefer to work with the FSM, then you can download it at:

Foxed.ca - Mazda RX-7 Manuals

Now you don't need to check every clearance listed. Make sure the irons are flat and that the coolant seal grooves are not destroyed. If the engine has not been overheated, inspect the housing chrome surface and decide if they are usable. If it has been severely overheated, measure housing width.

The apex seal grooves on the rotors are most important. Measure them first and if they don't spec out, discard the rotors are mill for 3 MM seals (probably cost less just to buy used good rotors). The grooves are the primary wear point on the rotors. I've never even bothered to measure side seal and corner seal grooves.

If the engine has over 100K on it, replace all bearings. Eccentrics just don't wear unless there was an oiling problem.

 

Your motor is a prime candidate for Alumaseal. Just don't screw up and get something different. Put it in the radiator, then either let it idle or (prefferably) take it for a spin around the block several times. Keep an eye on coolant levels until you are certain the leak is fixed. Could take anywhere from 5 minutes to a half hour.

$4.00 and you'll be back on the road with a smile on your face.

 

The car is on stands. Put in the alumaseal this afternoon, idled til warm, let it run 2500 revs for 15 minutes as smoke diminished, stepped it up to 3500 for ten minutes, smoke disappeared! Let it run another 15 minutes for good measure. The alumaseal is the shizzit, as my young staff would say. I'm a believer, this far in. I was starting to bum before finding your posts.

 

Coolant seals failures left unrepaired will errode the coolant seal grooves. If left too long you'll be looking for an iron on top of everything else.
THAT'S fact.

 

Okay, here's my story with Alumaseal/Bar's leaks. I bought an FD with bad coolant seals. And I know for a fact that the guy who sold me the car knew the seals were bad but he didn't tell me that. Oh well. The price was cheap enough that if I had to rebuild, I could. I put about 3000 miles on it after I bought it knowing that it was eating coolant slowly and I would just fill it up everyday. When the leak is slow and you drive daily, it isn't hard to do. Unfortunately, once they start eating coolant they start to like it and they eat more and more. When mine started getting progressively worse, I decided to do the BAR's Leaks, with aluminum in it. Poured in a half of bottle cold and ran it for like two hours. No more smoke on start up, no noticeable coolant loss....for about two days and 250 miles.

I open the ast cap when cold and I see all these fibers, like fiberglass, around the top of the cap. I pull that out and fish some more from the tank itself. Then a day goes by and my overflow hose pops off. I check it out and it's clogged with the same fiberous stuff. Clean it out and replace and top the car off with coolant and the next day, the overflow bottle gets clogged right at the top with the same crap.

I go for a drive that night and the thermostat ends up not opening at all. Gets hot but I shut it down and later get it home. Next morning going on my 120 mile drive to work, it runs a little warm, again thermostat didn't open right away but it finally did after massaging the upper hose. Made it to work and my other place and parked it.

One week later, I go to start it and no go. Take out the plugs and they are saturated with coolant. Yup, rebuild time. New plugs, got it fired up, smoked like crazy, and then got hot. This time, the thermostat wouldn't open at all.

My baby is now getting a new heart at Dr. Andy's, (my mechanic), to the tune of about three grand. I got to see the engine pulled apart and that fibrous stuff was in the coolant passages. Flushed the radiator and that stuff was in there too along with all these little fine pieces of aluminum.

Long story short, if you are on a trip or a long way from home and your car starts eating coolant and smoking then add this stuff. It will absolutely work temporarily to get you home or to the doctor for a rebuild. But if your coolant seals are bad, and I know this hurts, just get it to the mechanic or rebuild it yourself.

I got a mild streetport while I was at it.

Good luck!

 

That is true it happen to me

 

u could always try the raw egg into the radiator trick lol

 

Found the failure point in one combustion chamber. The metal on the coolant port side of the coolant seal broke off. So I am going to look at JB Welding it, then work it with a file and see how it looks when I am done. A Coolant seal failed in the other combustion chamber as well, but I think just a normal failure. Anyone have a cheap oring kit and maybe 2 piece Apex seals laying around?? I was hoping to not send too much putting this engine back together.

Thanks.

 

Is your car turbo or not. If it is turbo, i believe is better to rebuild the complete engine, and if necessary buy an use housing for good.

 

JB Weld? Buy a used iron or your doing the work for no reason and no gain. There are no cheap coolant seal kits. Get OEM and be done with it. If the hard seals are within spec, they can be reused but they MUST be replaced in the EXACT same position on the EXACT same rotor. Most recommend new springs.